Automatic yarn-knotting and tensioning device



Aug. 9, 1966 H. RAASCH AUTOMATIC YARN-KNOTTING AND TENSIONING DEVICE Filed March 20, 1964 AL M United States Patent 3,265,421 AUTOMATIC YARN-KNQTTING AND TENSIGNING DEVICE Hans Raasch, Rheydt-Odenkirchen, Germany, assignor to Walter Reiners, Monchen-Gladbach, Germany Filed Mar. 20, 1964, Ser. No. 353,358 Claims priority, application Germany, Mar. 21, 1963,

7 Claims. (Cl. 289-4) My invention relates to a yarn-knotting device of the type dscribed in US. Patents 2,981,559 and 3,110,511, for use in textile manufacture.

It often happens in yarn-winding machines having automatically operating knotting devices that many knotting failures recur one after the other at the same winding station. The faulty knots are traced to faulty yarn, a defect in the knotting device, or defective yarn guides. With automatic yarn-winding machines in which each winding station is provided with its own knotting device, a faulty knot or knotting failure necessitates a repetition of the knotting operation so that the knotting device is being continuously operated while the winding station is inoperative. Even more disadvantageous are those knotting failures that occur in automatic winding machines that are provided with a single knotting device for several winding stations such as is shown for example in Patent No. 3,030,040. When knotting failures occur at a single winding station in machines of this type, the knotting device is constantly monopolized by this winding station so that the operation of the other winding stations is retarded.

Counting devices have accordingly been provided in the past for winding machines which count the knotting failures per cop, per wound yarn length, per winding time or the like, and which prevent the start of a knotting operation when an adjustable limit of previous knotting operations is exceeded or signal the factthat the limiting amount has been exceeded or do both. The inspection devices or counting devices operate by the actuation of a special feeler after the tying of the knot and the movement of the feeler toward the yarn. If both yarn ends are not properly knotted together, however, no resistance is offered to the feeler. The feeler can therefore be moved farther and beyond the normal location of a knotted yarn so that it actuates the counting device, for example, through an electrical contact. F or these known knotting and control devices, a special operation is necessary to actuate the feeler to perform the inspection. Frequently, this inspection can take place only after the yarn-winding station has been turned on and after the therewith associated tautening or tensioning of the yarn. When yarn breaks are to be determined in addition to knotting failures, then the known devices become even more complicated in that an additional feeler for detecting the yarn breaks is necessary.

An object of my invention accordingly is to provide a yarn-knotting device which dispenses with all additional feeling or sensing devices known until now so that the winding machine is markedly simplified and its susceptibility to breakdown is reduced.

Another object of my invention is to provide a yarnknotting device which carries out the inspection operation during the knotting operation so that the time necessary for the inspection operation is accordingly economized.

With this in view and in accordance with my invention, I provide a yarn-winding machine with an automatic knotting device and with an inspection device that inspects the firmness of the knotted yarn. The knotting device has a tensioning member abutting against the properly knotted yarn, and a counting device which is actuatable by a releasing member cooperating with the tensioning member.

In accordance with other aspects of my invention, I provide one element of the knotting device with a releasing member which can actuate a counting device. The releasing member cooperates with the tensioning member in such a Way that each knotting operation is counted. The yarn breaks are simultaneously counted in the same way. It is, however, also possible to connect the releasing member with the tensioning member so that the counting device is actuated solely by a faulty knotting Operaton, while this tensioning member in a manner similar to that for the known feeler described above, can

also be moved a specific distance farther due to a knotting failure because no resistance is set up against it such as is provided when the yarn ends are suitably knotted.

In accordance with other aspects of my invention, not only is the counting device actuatable by the release member when a knotting failure is detected, but also the winding operation of the winding station is cut off. Then if necessary the counting device which registers the knotting failures for discontinuing the winding operation of the winding station can also be connected with the releasing member.

In the known devices the winding station is first switched on after the knot is tied, then the yarn is inspected and the winding station is again shut off if a knotting failure is detected. In the device constructed in accordance with my invention, however, the starting operation of the winding station does not take place until after it is established that a proper knot has been tied so that the surface of the take-up spool is not stressed by superfluous starting operations.

Although a knotting failure can occur at the first knotting attempt, i.e. the knot can be improperly tied, nevertheless, a proper knot can be effected at the second knotting attempt. It has become apparent that it is less advantageous in many cases for the number of knotting failures to be determined per supply coil, per yarn length or the like, than if the knotting failures are registered or recorded consecutively, and are erased either entirely or partly after a successful knotting operation as in accordance with a further aspect of my invention. The operation of a device having such features is as follows:

After a yarn break, the knotting device attempts to tie the broken yarn ends once again with each other. If a proper knot is thereby tied, nothing else occurs. When a knotting failure, however, takes place, i.e. when the yarn ends are not tied properly to one another, the associated counting mechanism is actuated and is advanced one scale graduation or the like. A second knotting attempt then takes place immediately thereafter or following a specific interval. If the second knotting attempt is again unscuccessful, the counting mechanism is advanced another unit graduation. If the second knotting attempt is successful however, then the counting device is switched back to zero. In a similar way it can be determined when a third, fourth or further knotting attempt finally succeeds in tying a proper knot, in which case, however, the counting device is not switched entirely back to Zero but rather only to a predetermined value of counter units. It must accordingly be taken into consideration that only a predetermined number of knotting attempts have thus been carried out, for example four or five, and for the adjusted number, that is for four or five unsuccessful knotting attempts, the winding station is shut off. The advantage of this procedure consists in that on the one hand, as with the known methods, the length of time during which the winding station is serviced by the knotting device is not reduced, and on the other hand, however, the knotting failures do not add to the total unwinding time of the supply coil or cop. If the number of knotting failures were, for example, limited to three, i.e. the winding station were to shut down after the third knotting failure, it could happen that immediately after the beginning of the winding operation two knotting failures might occur, yet a properly tied knot could be effected at the third knotting attempt. Then if further knotting failures should occur at any time during the unwind ing of this supply coil, the winding station would already be shut off. If, however, after each successful knotting attempt the counting mechanism is reset to zero, then in fact only the consecutive knotting failures are counted, without the amount of knotting failures occurring at one position of the supply coil having any effect thereon, as additional knotting failures often occur in the further course of the winding operation.

Other features which are considered as characteristic for the invention are set forth in the appended claims.

Although the invention has been illustrated and described as embodied in an automatic yarn-knotting device, it is nevertheless not intended to be limited to the details shown, since various modifications and structural changes may be made therein without departing from the spirit of the invention and within the scope and range of equivalents of the claims.

The construction and method of operation of the invention, however, together with additional objects and advantages thereof will be best understood from the following description of specific embodiments when read in connection with the single figure in the accompanying drawing which is a partly diagrammatic sectional view of a yam-knotting device and associated elements constructed in accordance with my invention.

Referring now to the single figure of the drawing, there is shown a knotting device such as is disclosed in US. Patents 2,981,559 and 3,110,511. Two'coaxially mounted cam discs 6 and 7 are provided that perform a single full rotation clockwise during each knotting operation in the direction of the arrow 22 for actuating the knotter. A follower arm 8 rests against the cam 6 and is rigidly joined with the gear segment 9 which is spring-biased in a clockwise direction. The gear segment 9 is in meshing engagement with an angularly related spur gear 10 that is mounted on a hollow or tubular shaft 23 which carries a cup-shaped disc 11. Two tie beaks 12 and 13 joined to driving pinions are actuated in a known manner by the cup disc 11 which is provided with peripheral teeth meshing with the driving pinions. An adjustable set screw or follower pin 15 engages the surface of the cam 7 and is mounted in a bore formed in one arm of a bell crank lever 14 and biased away from the lever 14 by a spring 24. A forked tensioning member or tappet extends through the hollow shaft 23 and is pivotally connected at one end to the upper end of the lever 14. The lower end of the lever 14 carries an electric contact 16 cooperating with a fixed contact 17 provided at one side of an aperture formed in the housing of the knotting device. A counting device 26 is serially connected with the contacts 16, 17 and a current source 25. For winding machines in which a single knotting device services several winding stations, it is necessary to provide each winding station with its own counting device. When relative movement occurs between the counting devices secured to the winding stations and the releasing member, as exemplified by the contacts 16, 17 and the associated electric circuit, connected with the knotting device, sliding contacts such as are shown diagrammatically at 27 and 28 for example can maintain electrical connection. Rotation of the cam 6 in the direction of the arrow 22, causes the follower arm 8 and the gear segment 9 to turn the spur gear and the cup disc 11 so as to actuate the tie beaks 12 and 13 to tie a knot in a manner generally known and described more fully in Patents Nos. 2,981,559 and 3,110,511. Rotation of the cam 7 occurs simultaneously with that of cam 6. The set screw which engages the camming surface of the earn 7 acts through the spring 24 on the lever 14 and moves the tensioning member 5 in the direction of the arrow 5 while and after the knot is formed. If a proper knot is formed by the k-notter, then the bifurcated end of the tensioning member 5 can abut against the yarn ends 1 and 2 now knotted together, and the residual upward motion of the set screw 15 is then taken up by compression of the spring 24. At a knotting failure, however, the tensioning member 5 encounters no resistance from the yarn and can swing out to the location shown in phantom by the dot-and-dash lines so that both contacts 16 and 17 are mutually engaged or closed as the lever 14 is caused to turn counterclockwise. The counting mechanism 26 is thereby energized and records an advance of one scale division or counter unit. The knotting device proper then leaves the winding station and for the time being services other inactive winding :stations or winding machines in a manner described for example in Patents Nos. 3,033,478 and 3,078,054. When the knotting device returns each time to this winding station at which the knots are not properly produced, repeated knotting attempts are then carried out. If the knotting attempt is successful, i.e. if the yarns from the supply coil and the take-up spool become properly tied to one another, then, as has been mentioned 'hereinabove, the complete upward movement of the set screw 15 with respect to the bell crank lever 14 is not carried out but rather a part of this movement is taken up by the compression of the spring 24. Nevertheless, the set screw 15 is pushed a suitable distance upwardly out of the guiding bore in the bell crank lever 14, so that, as shown in the illustrated embodiment, the contact pair 31, 32 is closed. One of the contacts 31 is carried at the end of an arm extending from the lever 14 and the other of the contacts 32 is of the leaf spring type carried on the set screw 15. This contact pair 31, 32 closes a circuit 33 which effects the resetting of the counter mechanism to zero in a wellknown suitable manner. As illustrated, the connection between the contacts 31, 32 to the circuit of the counting mechanism can be made with sliding contacts similar to the sliding contacts 27 and 28. If a second knotting attempt also fails, then the counting device is again advanced another counter unit. The knotting device then leaves the winding station once again to service the other stations and returns anew after a specific interval to carry out a third knotting attempt, and more if necessary. If a number of knotting attempts to which the counting device had previously been adjusted are failures, and this number has been cumulatively recorded by the counting device, the winding station is then shut oif in a manner known to the man of ordinary skill in the art by a device such as is shown for example in Patents Nos. 2,716,004 and 2,752,103 so that further knotting attempts are prevented.

Thus when the counter 26 records the preset limit of knotting failures, a wiper engages the contact C which energizes and activates a solenoid R to shut ofl? the winding operation at the winding station.

Known mechanical or electrical counting mechanisms can be employed in the counting device and also mechanisms which operate by storing up heat, pressure, electricity, volume or the like. My invention, however, is not limited to the described use. It can also be employed for winding machines in which each of the winding stations has its own knotting device, as well as for winding machines that have winding stations and knotting devices that are movable with respect to one another.

I claim:

1. In a knotting device, means for knotting a pair of yarn ends including tensioning meansnorrnally tensioning the ends knotted thereby so as to test the firmness thereof, said tensioning means being movable to a predetermined location when the knotting is faulty, and counting means operatively connected to said tensioning means for recording a faulty knotting whenever said tensioning means is moved to said predetermined location.

2. In a knotting device, means for knotting a pair of yarn ends including tensioning means normally tensioning the ends knotted thereby so as to test the firmness thereof, said tensioning means being movable to a predetermined location when the knotting is faulty, releasing means associated with said tensioning means and responsive to the movement of said tensioning means to said predetermined location, and counting means actuated by the response of said releasing means to said movement of said tensioning means for recording a faulty knotting whenever said ten-sioning means is moved to said predetermined location.

3. In a knotting device, means for knotting a pair of yarn ends including tensioning means normally tensioning the ends knotted thereby so as to test the firmness thereof, said tensioning means being movable to a predetermined location when the knotting is faulty, a releasing member connected to said tensioning means and movable with said tensioning means, and counting means actuated only in response to a faulty knotting by the movement of said releasing member for recording the faulty knotting whenever said tensioning means is moved to said predetermined location.

4. A knotting device according to claim 2, wherein said releasing means includes a pair of contacts movable into electrical engagement with each other by said tensioning means for energizing a circuit, said counting means being electrically connected in said circuit and capable of recording a faulty knotting whenever said circuit is energized.

5. In a yarn-winding machine, a winding station for performing a yarn-winding operation, a knotting device located at said station comprising means for knotting a pair of yarn ends including tensioning means normally tensioning the ends knotted thereby so as to test the firmness thereof, said tensioning means being movable to a predetermined location when the knotting is faulty, and counting means operatively connected to said tensioning means for recording a faulty knotting whenever said tensioning means is moved to said predetermined location, said counting means being connected with said winding station for shutting off the yarn-winding operation after a pre-adjusted number of faulty knottings are recorded.

6. In a knotting device for knotting a pair of yarn ends, tensioning means movable into abutment with the knotted yarn ends for tensioning the same when properly knotted, said tensioning means being movable to a prede termined location when the knotting is faulty, counting means operatively connected to said tensioning means for cumulatively recording a series of faulty knottings when said tensioning means is repeatedly moved to said predetermined location, and reset means actuated by said tensioning means for resetting said counting means to a recording position prior to the cumulative recording of said series of faulty knottings when the yarn ends are properly knotted and said tensioning means is moved into abutment therewith.

7. In a knotting device for knotting a pair of yarn ends, tensioning means movable into abutment with the knotted yarn ends for tensioning the same when properly knotted, said tensioning means being movable to a predetermined located when the knotting is faulty, counting means operatively connected to said tensioning means for cumulatively recording a series of faulty knottings when said tensioning means is repeatedly moved to said predetermined location, first releasing means including a first circuit and a first pair of contacts in said circuit movable into electrical engagement with each other in response to the movement of said tensioning means to said predetermined location for energizing said first circuit, counting means electrically connected in said first circuit and capable of re cording said series of faulty knottings when said first circuit is repeatedly energized, and second releasing means including a second circuit and a second pair of contacts in said circuit movable into electrical engagement with each other in response to the movement of said tensioning means into abutment with the knotted yarn ends, when the ends are properly knotted, for energizing said second circuit, said counting means being electrically connected in said second circuit and capable of being reset to a recording position prior to the cumulative recording of said series of faulty knottings whenever said second circuit is energized.

References Cited by the Examiner UNITED STATES PATENTS 2,834,207 5/1958 Chamberlain et al. 2864 X 2,981,559 4/1961 Furst 28912 X 3,063,007 11/1962 Baugh et a1 2864 X 3,110,511 11/1963 Gebald et a1 28912 MERVIN STEIN, Primary Examiner.

ROBERT R. MACKEY, Examiner.

L. K. RIMRODT, Assistant Examiner. 

1. IN A KNOTTING DEVICE, MEANS FOR KNOTTING A PAIR OF YARN ENDS INCLUDING TENSIONING MEANS NORMALLY TENSIONING THE ENDS KNOTTED THEREBY SO AS TO TEST THE FIRMNESS THEREOF, SAID TENSIONING MEANS BEING MOVABLE TO A PREDETERMINED LOCATION WHEN THE KNOTTING IS FAULTY, AND COUNTING MEANS OPERATIVELY CONNECTED TO SAID TENSIONING MEANS 